Means for ramming rock by short rammers in very deep water



Aug. 17,1926. 1,596,341

M. E. P. E. DOBMOY MEANS FOR RAMMING BOOK BY SHORT RAMMERS-IN VERY DEEP WATER Filed Sept. 4, 1924 2 Sheets-Sheet 1 v [/7 ran 70/ firz Z/fi Aug. 17 1926.

- M. E. P. E. DORMOY Y SHQRT RAMMERS IN VERY DEEP WATER Fil ed Sept. 4, 1924 MEANS FOR" RAMMING ROCK B 2 Sheets-Sheet 2 Y M w. V M 2 2 j Patented Aug. 17, 1926 UNITED sr rss 1,596,341 PATENT orFicE.

MARIE ETIENNE PAUL EMILE DOEMOY, OF PORT-TEWFIK, EGYPT.

MEANS FOR BAMMING ROCK BY SHORT BAMMERS IN VERY DEEP WATER.

Application filed. September 4, 1924, Serial No. 735,939, and in France September 21, 1923.

Up to the present time, ramming opera tions upon rock bottom in the various navigation ports or channels have been carried out by the use of pontoons provided with 5 rammers which are'guided at the level of the deck. In order to carry out the ramming operations at the prevailing depths which are at the present time 12 metres of water, corresponding to the draught of lo modern vessels, and in order to meet the dif ficulties due to the tides in numerous cases, the practice has been to make use of rammers" of metres whichare very expensive as well as is easily broken. In these conditions, it became of interest tofind Whether by the use of much shorter ram1nersfor instance some metresit would be feasible not onl'y to attain the 12 metres bottoms but if necessary to break the rock with facility as far as metres depth.

The presentinvention-relates to a method and means whereby such operations can be carried out. By the said method, the ramas mere are no longer guided at the level of the deck of the pontoon upon which they are mounted, but at a point below the deck of the pontoon, and by means of a device which is supported below the pontoon by means of elements having a great elasticity and so disposed that it'can be raised and lowered according to the depth" at which the ramming operation is to be perfoanec so that the upper part or head of the rammer or rammers shall in no case become disengaged from the guiding portion, and the said method will therefore enable the use of rammers of much shorter length than the ones now in use, 'these being'also of an entirely cylindrical shape.

The said device essentially consists of a timber guiding. frame which is strengthened by a metallic structure and comprises aper- 7 turns for the passage of the rammers, the said frame also serving to guide the ram mers jth'e frame is supported below the pontoon by means of suspension chains whereby it is possible to adjust the height at which the said frame is to be supported,

7 i and also by means of slackene'd chains conexample the arrangements by which the invention is carried into effect, comprising an apparatus with two rammers', but obviously the invention is not limited to this number of rammers. Y i v Fig. l is a side elevation of the pontoon supporting the guiding frame, the latter'being shown in section upon a plane passing through the centre line of one ofthe ramm ers'.

Fig. 2 is a plan view of the de ck of the pontoon. i Fig. 3 is a vertical cross section of the pontoon according to a plane passing through the centre line of the rammers and perpendicular to the lon 'itu dirial axis "or the pontoon. I Fig. 4 is a like section showing the arrangement for raising the guiding frame. Fig. 5 is a section on a larger scale show ing the upper partof a short cylindrical rammer.

Referring now to the drawings the pontoon 1 is provided at its middle part with a supporting structurecom prising two up-.

rights 2 and a strut 3, said structure being adapted to support the pulleysa co-operat ing with the hoisting cables 5 serving for the operation of theramming device 7 and actuated by'the hoisting winches 6. The above ,inentioned mechanism as'a whole is well lrnown, and is indicated solely byiway of reference. Y

Between the two uprights 2 a vertical aperture or well 8 for the passage the rammers. A guiding frame 9, through which the rammers may vertically slide, is suspended from the pontoon belowsaid well. This frame consists of successive layers of hard wood blocks disposed so as to alternately cross each other at right angles and strengthened by a metallic reinforcing structure comprising, upon .the lower face of said body, a thick metal plateand upon the upper face .a like plate upon which is disposed a, forged steel frame, the whole being cross-braced by numerous bolts. The central part of the-guiding frame is providedwith holes 10 for the passage and the guiding of the rammers 7. Said holes may be pierced in bearings built up of layersof hard wood with each layer arranged with the grain at rightangles to thatof the preceding layer with crossed grain, which are mounted in the said frame'in such manner that they can be removed and replaced af.

ter wear.

It is important that the guiding frame should have a relatively great WQlQllt, so

as to reduce the whipping action of the rammers h its inertia. Experience seems to prove that the said weight will have the proper action when it represents from one third to one-quarter die weight of the rammer. The said frame is suspended from the hull of the pontoon by four chains or other suitable connections secured to the pontoon and. passing nearly vertically through the said well 8. Moreover four additional chains 11 or the like passing around the hull of the pontoon connect the latter to the said guiding frame. These four chains have a certain amount of slack, and are provided intermediate their ends with four stretching weights 12 which ensure the regular tension of said chains 11 while allowing a certain swinging of the frame in all directions and the return of the latter to the initial position which is its middle position of equilibrium. In fact, said chains 11 act like springs having a perfect elasticity. Further, the flexibility of this suspension device avoids any disastrous breakage of the chains which could be occasioned by the whipping action of the rammers.

The depth at which the guiding frame 9 is suspended is regulated by adjusting the length of the inner chains 13 secured to the pontoon. The chains 11, 13 and 1a are secured to the frame 9 through the medium of the anchoring plates 15, Fig. 2, which are bolted to the upper face of the said frame and are provided with suitable apertures or rings. To this plate 15 are also secured chains or cables 14, removably attached at their other end to the pontoon and having normally a certain slack whenthe supporting chains 13 are tensioned. These chains or cables 14 serve to adjust the depth of the guiding frame as later described. Obviously, the pontoon with the apparatus mounted thereon is provided with suitable means by which it can be displaced and brought to the place of Work with due facility. In order that the pontoon shall on no account be stopped in a frequented channel by reason of an accident such as the breakage of the hoisting cables 5 actuating ,the rammers, provision may be made of the following safety device.

An auxiliary hoisting cable 16 is removably secured to the upper crosspiece of the supporting frame, and in order to prevent any rocking motion of the said cable, its lower end is attached to one of the uprights 2 by means of a suitable cord 16".

Two cables 16 are also removably attached to the upper cross-piece of said frame and are secured to the uprights at 17. Further, safety cables 18, Fig. 3, are attached to the upper ends of the rammers together with the hoisting cableso, and are secured at 20 to the latter cables and at 19 to the uprights 2 in such manner as to offer a sufficient slack in order not to interfere with the operation of the manners. The upper end of eachrannner is provided with a transverse aperture 21 into which an iron rod can be inserted.

The adjustment of the depth of immersion of the guiding frame 9 is performed as follows. The rammers are suitably raised or lowered by means of the hoisting cables 5 and winches 6 so as to bring the upper ends of said rammers on a level with the deck of the pontoon. Then iron rods are inserted into the apertures 21 in the upper ends of the rammers, and the chains or cablesle' are attached to the said rods (Fig. 4t). The guiding frame can now be raised or lowered by means of the same hoisting cables 5, the chains 11 and 13 being slackened or tight ened according to needs. The said frame can thus be placed at a suitable depth in order that the rammers may reach the bottom without disengaging the upper part from the guiding portion of the said frame. l i hen the desired depth is reached, the chains 11 and 13 are secured and the chains or cables 14 are disconnected from the apertures 21 and attached again to the pontoon.

iii)

In case of rupture of the hoisting cable 5 end of said cable 16 is then attached to the.

safety cable 18 under consideration, whereby it is possible to raise the rammer which has remained upon the sea bottom. Said rammer is then retained at the desired height by securing'the corresponding cable 16 to the iron rod which has been.

inserted into the aperture 21. The neces sary repairs or renewals may now be carried out.

Rammers of only ten to twelve metres length will operate in an excellent manner in these conditions. Such short rammers differ considerably from the long type which is in current use. Usually the upper part of the known rammers, especially the long rammers has a tapered form with decreasing cross section from bottom to top, with'the object of lowering the centre of gravity of the rammer below its centre of figure, i. e. below the middle point of its length, so that the upper part of the rammer has a smaller diameter than the lower part. Short rammers of this type, say rammers of less than twelve metres length, when used in conjunction with the ramming device according to the invention, afford a great drawback. At the moment when a short rammer of this type strikes the rock, its reduced part engages the guide with a certain play and the whipping movement of the rammer causes strokes that are most prejudicial to the preservation of the cables, of the rammer, and even of the guide.

According to the invention the rammer is made in the cylindrical form throughout the whole length, but in order to preserve the advantage resulting from the lowering of the centre of gravity, the upper part of the rammer has formed therein a longitudinal tapered recess of suitable dimensions, which is indicated by 22 in Fig. 5, and serves to lighten the upper part of the rammer with respect to the lower part, and in this manner the centre of gravity of the rammer can be lowered while at the same time the whipping effect is diminished.

It will be thus observed that the said invention offers the following advantages:

1. Total suppression of arring motion of the hull of the pontoon, which is the occasion of frequent and expensive repairs.

2. Excellent preservation of the guiding frame which in the known devices is out of the water and is rapidly deteriorated by the whipping action of the rammers.

3. Diminution to a great degree of the continual rupture, at the top of the rammers, of their suspension cables owing to the damping of the whipping motion of the cables within the mass of liquid.

4. The rammers will now last for a practically indefinite period, since they are subjected to no lateral stresses, thus ofiering a considerable economy.

5. The ramming efficiency obtained with the short type of rammer i. e. one which is of lighter weight, is by no means reducedby the use of the said arrangement. In fact, the shocks and jarring of the rammer and the guiding frame are so much reduced that there is now no inconvenience in dropping the short rammers from a much greater height, for instance double the distance, so as to obtain the same kinetic energy, as by the use of long rammers.

Obviously, the said arrangement is sus.

cept-ible of numerous modifications without departing from the principle of the invention.

Having now described my invention, what I claim and desire to secure by Letters Patent is:

1. In an arrangement for the ramming of the rock under water at great depths by means of short rammers, the combination with a pontoon of a short rammer, a flat guiding frame adapted to guide said rammer over a short length only, whereby the whipping action of said rammer does not practically affect said guiding frame, an-

choring means secured to said guiding frame, flexible connections secured to said anchoring means for suspending said guiding frame from the pontoon at a lower level than the bottom of same, operating means for the rammer and means for temporarily connecting said guiding frame to the head of the rammer.

In an arrangement for the rammingof the rock under water at great depths by means of short rammers, the combination with a pontoon of a short rammer, afiat ponder'ous guiding frame adapted to guide said rammer over a short length only and to oppose any whipping action of said rammer, anchoring-means secured to said guiding frame, flexible connections secured to said anchoring means for suspendin said guiding frame from the pontoon at a ower level than the bottom of same, operating means for the rammer and means for temporarily connecting said guiding frame to the head of the rammer.

8. In an arrangement for the ramming of the rock under water at great depths by means of short rammers, the combination with a pontoon of a short rammer, a flat ponderous guiding frame, the weight of which is comprised between one third and one quarter the weight of a rammer and adapted to guide said rammer over a short length only, and to oppose any whipping action of said rammer, anchoring means secured to said guiding frame, flexible connections secured to said anchoring means for suspending said guiding frame from the pontoon at a lower level than the bottom of same, operating means for the rammer and means for temporarily connecting said guiding frame to the head of the rammer.

4. In an arrangement for the ramming of the rock under water at great depths by means of short rammers, the. combination with a short rammer, of a pontoon provided with a vertical aperture for the passage and operation of the rammer, a guiding frame for the rammer, inner suspension chains passing through said aperture and attached at their ends respectively to the pontoon and to the frame, whereby the latter is suspended from the pontoon at a lower level than the bottom of the same, outer suspen sion chains attached at their ends respectively to the outer edges of the hull of the pontoon and to the frame, stretching weights provided on said outer chains intermediate the ends thereof for tensioning the chains while allowing the frame to oscillate about a. middle position of equilibrium.

5. In an arrangement for the ramming of the rock under water at great depths by means of short rammers, the combination with a short rammer, of a pontoon provided with a vertical aperture for the passage and operation of the rammer, means for raising and lowering the rammer, a guiding frame for said rammer, flexible means for suspending said frame "from the pontoon below said aperture and at a lower level than the bottom of the same, a cable attached at one end to said trams: means for removably attaching the other end of said cable to the rammer, a metallic bar adapted to be introduced into a trensversal bore in the head of the rainmor "for remorably attaching the said other end of said. cable whereby the depth of the frame can be adjusted according to the depth of ramming.

6. in an arrangement for the ramming of the rook under water at great depths by ity of the rammer is lowered, a flat ponder ous guiding frame provided with a Vertical cylindrical opening for the passage of the rammer, flexible means for suspending said frame from the pontoon at a lower level than the bottom of the same, and means for operm-ing said rammers.

In testimony whereof I have signed my name to this specification.

MARlE ETIENNE PAUL EMILE DORMOY. 

